This invention relates to an electronic musical instrument, more particularly an electronic musical instrument which automatically performs a counter line melody in the music being played.
A prior art electronic musical instrument which automatically performs a counter melody together with an accompaniment chord is disclosed, for example, in Japanese Preliminary Publication of Pat. No. 72213 of 1977. In the prior art automatic counter melody performing device disclosed therein a specific note among accompaniment chord constituting tones is used as the counter melody note so that the produced counter line melody lacks variety. For example, the specific note may be the root note of a chord, and where the root note is predetermined to be a counter melody note, only the root notes of the chords are used as the counter melody notes. Where either the 3rd degree note, 5th degree note, or the highest note played in the lower keyboard (a chord performance keyboard) is predetermined as the specific note, the counter melody notes are always fixed to such determined notes, only a monotonous counter line melody is produced, thus failing to realize an interesting musical performance. For instance, where the root notes are used as the counter melody notes, when the accompaniment chord changes from C major chord to A minor chord and then to C major chord, the counter melody note changes from the C note to the A note but it then returns again to the C note. Generally, the number of kinds of the chords utilized in one music is limited by the performance tonality of the music and so that in most cases a limited number of chords are repeatedly used. Consequently, in an actual music performance, the same note might be used repeatedly very often, if the same chord is repeatedly used.